Tube cleaner



J. R. TURNER TUBE CLEANER Dec. 28, 1937.

Filed April 15, 1935 FIG.

FIG.

FIG.

FIG.

INVENTOR JOHN R. TURNER Patented Dec. 28, 1937 UNITED STATES mosses) TUBE CLEANER,

John R. Turner, Chicago, Ill.,

versal Oil Products Company, Chicago,

assignor to Uni- Ill., a

corporation of Delaware Application April 15, 1935, SerialNo. 16,292

3 Claims.

This invention particularly refers to an improved form of cleaning device for removing deposits of solid materials such as coke or calcareous deposits from the inner surface of tubular elements.

It has been common practice for many years 'to clean the interior surface of tubular elements in steam boilers, oil heaters and the like, for the purpose of removing therefrom deposited coatings of calcareous or carbonaceous material, by means of a tube cleaner comprising reamers of the form generally known as star cutters on arms which are rotated by means of an air or steam driven turbine, electric motor or the like. In such cleaners there is generally a considerable amount of play in the cutter or cutter arms so that they may be readily inserted in the tubes to be cleaned and the centrifugal force generated by the rotation of the cutter assembly serves to force the cutters against the walls of the tube so that they may exert a cutting action on the material to be removed therefrom. This principle of operation has proven very successful with tubes of relatively large internal diameter, (i. e. 3 inchesor more) but with smaller diameter tubes the relatively short throw of the arms does not generate sufficient centrifugal force to cause the cutters to dig into the relatively hard coke and calcareous deposits and as a consequence the cutter tends to run idle in the tube at high speed without exerting any efiicient cutting action upon the deposited material in the tube. When, on the other hand, a cleaner such as a drill or reamer substantially the same size as the internal diameter of the tube is employed a very small amount of wear on the cutting surface soon renders it useless and there is also a tendency when the cutter is new for it to dig into the metal surface of the. tube, particularly when the tube is slightly warped or out of round, as is frequently the case, while on the other hand if the tube is bulged or slightly irregular in internal diameter the cutter will leave patches or spots which are not properly cleaned. t

The present invention provides a tube cleaner employing the same general principle of utilizing centrifugal force for exerting pressure between the cutting surfaces and the material to be removed which differs, however, from previous cleaners of this general type in that the arms to which the reamers or star cutters are attached are weighted so as to increase the centrifugal force generated for the same length of cutter arm. This featuie renders the device of the present invention particularly advantageous in the cleaning of relatively small diameter tubes and it also increases the efficiency of cleaners for larger tubes.

In the preferred embodiment of the present invention, the cutter arms are considerably heavier 5 than required for adequate structural strength and are pivoted to each other and to the rotatable shaft of the cleaner near the central point in their length, the cutter arms crossing the axis of rotation at the pivotal point, so that the sections of the cutter arms on either side of the pivoting point, in being flung outward when the assembly is rotated, will exert an outward-moving pressure on the cutters. The central pivoting of the cutter arms reduces the length of the section of the arms from the pivotal point to the cutters, thereby decreasing bending ofthe arms and rendering the cleaner more rigid and sturdy.

The accompanying diagrammatic drawing illustrates one specific form. of the, device of the present invention. Figure l is a plan view looking toward the end of the cleaner to which the cutters are attached. Figure 2 is a sectional elevation of the same cleaner taken along a plane indicated by the line 2-4 of Figure 1. Figure 3 is another plan view of the ,same cleaner shown at right angles to the view of Figure 1 and with the cutter arms expanded. Figure 4 is an elevation of the same cleaner corresponding to the plan view of Figure 3.

The rotatable shaft I of the cleaner has, in the case here illustrated, a threaded recess 2 in its lower end which serves as a means of attaching the cleaner to the shaft of -a suitable motivating. means such as an air or steam driven turbine, electric motor or the like. The upper end of shaft l is screwed into a cap .3 in which the opposite halves 4 and 5 of a split pin are held by means of a tongue and groove arrangement indicated at 6 between the shaft l and the pins 4 and 5. A key 1 extending through the top of cap 3 into the pins 4 and 5 at their junction serves to prevent the pins from turning. Weighted arms 8 and 9 are held in pivotal relation to the shaft I and cap 3 by means of pins 4 and 5 and cutters such as indicated, for example, at Ill and llare attached to the upper end of each of the arms 8 and 9 by means of a cap I2. In the particular case here illustrated the arms 8 and 9 are semi-cylindrical, the two arms forming a slightly tapered cylinder, the upper portion of which is cut or split along a helical contour and the lower portion of which is split axially. In this manner as much mass and weight is added tube to be cleaned.

The arms 8 and 93 are around or otherwise tapered to conform to the general contour illustrated in the drawing so that when they are ex pended in wormng position only the cutters come in contact with the inner surface of the tube or the material being removed therefrom.

It will be understood that the invention is not limited to the specific form of apparatus illustrated and above described, since other forms using the same principle of weighted arms may be devised by a skilled mechanic from the teachings of the present invention.

The term weighted arms as used in the speci fication and appended claims of the present case is intended to designate pivoted members of the tube cleaner which support the cutters and which have a greater mass and consequently greater weight than that required for adequate struc= tural strehgtl'l.

I claim as my invention:

l. A rotary tube cleaner comprising, in oom= hinatioh, a central. shaft, means for attaching one end of said shaft to a rotary motivating means, a cap attached to the opposite end of said shaft, transverse through the sides of said caoahd held in place by to the arms as can he conveniently inserted in the stationary pins extending said shaft, weighted arms pivotally attached to said cap by means of said. pins and extending generally parallel to the shaft, and cutters attached to one end of each of said weighted arms. 2. A rotary tube cleaner comprising, in comhination; a central shaft, means for attaching one end of said shaft to a rotarymotivating means, a cap attached tothe opposite end of said shaft, transverse stationary pins extending through the sides of said cap and held in place by said shaft, weighted arms extending generally parallel to the shaft and. crossed near their central portion and pivotally attached; at their point of juncture, to said cap by means of said pins and cutters at= tached to one end of each of said weighted arms.

3. A rotary tube cleaner comprising a rotat= able shaft, arms pivoted on a transverse axis to the shaft intermediate their ends and extending generally parallel to the shaft, said arms crossing each other and the axis of rotation of the shaft at the pivotal point, and cutter means attached to one end of each of the arms and adapted to C0l1== tact the inner surface of the tube being cleaned upon rotation of the shaft, the opposite ends of the arms being tapered toward the shaft to re tate within the tube out of contact with the surface thereof JQHN it. NEH. 

